A Cephalic Central Ray Angulation Is Required on an AP

Multiple Choice

A cephalic central ray angulation is required on an AP knee projection when the
1) examination is performed with the patient in an upright position.
2) patient's anterior tibial margin is demonstrated distal to the posterior tibial margin on the resulting image.
3) the patient's ASIS to imaging table measurement is 22 cm.
4) the knee is flexed and a curved IR is used.

A) 2 and 3 only
B) 4 only
C) 2 and 4 only
D) 1, 2, and 4 only